NASCAR details the post-race inspection process

The Iowa Speedway race winner was disqualified on Sunday; Here’s how that process works

The Monster Energy NASCAR Cup Series no longer has a ride height rule. However, the truck series and Xfinity Series still have the rule.

There’s an argument that getting the cars off the ground make for better racing. But, that’s not the purpose of a ride height rule. Ride height rules save the teams from themselves.

The lower teams can get the cars, the better they are going to handle. Sometimes, dragging the body or chassis on the ground can make cars faster.

But, it’s expensive to drag carbon body parts or frames across the race track. The ride height rule keeps the teams from wearing out the equipment over 250 laps.

Ross Chastain failed that ride height rule in the NASCAR Truck Series race at Iowa Speedway. As a result, his race win was taken away.

These detailed inspections aren’t new but the location of them is. Previously, cars and trucks were taken back to the NASCAR R&D Center for a tear down inspection in North Carolina.

This year, NASCAR is doing most of that same inspection, at the track. It allows NASCAR to get away with encumbered finish announcements on Tuesday.

Now, the winner can be officially announced about 90 minutes after the race is over. In this case, the race win was taken away and handed to the 2nd place finisher of Brett Moffitt.

Wayne Auton explains the NASCAR post-race inspection process

“It doesn’t matter which series it is of the three national series. Everybody’s pushing everything to the limit,” Wayne Auton explained on ‘The Morning Drive’ via Sirius XM NASCAR Radio.

“At the end of the race, you’ll see all three series pull cars out to the side. We have officials that stay with those cars until it gets to the inspection area.”

“Once it gets to the inspection area, the air pressures are checked. Then, it gets rolled up onto the height station.”

“Pre race, there’s a really narrow window that they have to start the race in. In post-race, that window opens up for tolerances of running on the race track.”

“The truck is checked. They take it off, roll it around and let it sit for a little bit to see if it comes back up. I was told the truck exceeded those limits of being way too low.”

“It’s not like you start the race with a 3/8″ tolerance on the height sticks. It opens up pretty good, to probably an inch or inch and a half tolerance.”

“You have green, yellow and red. It seems unfortunately that the truck of Ross Chastain went into the red area.”

The team is then informed they would be disqualified. The information is passed to Chad Little and he writes up the penalty at the race track.

The team has the option to appeal the penalty, which they have in this case. On Wednesday, that appeal case will be heard. If they fail the appeal, they an option to send appeals officer for final review.

Carbon body panels make NASCAR Xfinity Series inspection easier

“In the NASCAR Xfinity Series, we tore three cars down to the ground basically.”

“We told everybody we would try to have everything done in about a 90 minute window. The cool thing about the NASCAR Xfinity Series is we can take a whole side off of a car.”

The NASCAR Xfinity Series bodies are the same on all the cars. The carbon bodywork is hung and bolted on. That also makes inspection easier on the officials.

“We’ll take trailing arms out, we’ll take shocks apart, we’ll take springs and measure them. There’s a lot of things we can do in that post-race inspection that used to take 3-4 hours. We’ve toned that down but we’re still looking at the same parts.”

Which NASCAR race cars get inspected after the race?

In the Monster Energy NASCAR Cup Series, all of them get inspected for lug nuts. But, three of them get the more detailed rear down process.

The winner is always one of those cars selected. Most of the time, 2nd place is another car selected. A third car is picked at random at a random draw. The random car is selected ahead of the start of the race.

“I’m very proud of the way our process works,” Auton continued.

“There have been times were in the Xfinity Series, we see teams pushing the limits before the race. Lo and behold, their number comes up somehow, mysteriously.”